<template>
  <div>
    <!-- 评论列表 -->
    <div class="cmt-list" :class="isShow ? 'art-cmt-container-1':'art-cmt-container-2'">
      <van-list v-model="loading" :finished="done" finished-text="我是有底线的" @load="pullUpLoadMoreFn"
        :immediate-check="false" offset="80">
        <!-- 评论的 Item 项 -->
        <div class="cmt-item" v-for="obj in commentList" :key="obj.com_id">
          <!-- 头部区域 -->
          <div class="cmt-header">
            <!-- 头部左侧 -->
            <div class="cmt-header-left">
              <img :src="obj.aut_photo" :alt="obj.aut_name" class="avatar">
              <span class="uname">{{obj.aut_name}}</span>
            </div>
            <!-- 头部右侧 -->
            <div class="cmt-header-right">
              <van-icon name="like" size="16" color="red" v-if="obj.is_liking"
                @click="likeOrDislikeFn(obj)" />
              <van-icon name="like-o" size="16" color="gray" v-else @click="likeOrDislikeFn(obj)" />
            </div>
          </div>
          <!-- 主体区域 -->
          <div class="cmt-body">
            {{ obj.content }}
          </div>
          <!-- 尾部区域 -->
          <div class="cmt-footer">{{ $timeAgo(obj.pubdate) }}</div>
        </div>
      </van-list>
    </div>
    <!-- 底部添加评论区域 - 1 -->
    <div class="add-cmt-box van-hairline--top" v-if="isShow">
      <van-icon name="arrow-left" size="0.48rem" @click="$router.back()" />
      <div class="ipt-cmt-div" @click="isShow = false">发表评论</div>
      <div class="icon-box">
        <van-badge :content="totalCount" max="99">
          <van-icon name="comment-o" size="0.53333334rem" @click="scrolllntoViewFn" />
        </van-badge>
        <van-icon name="star-o" size="0.53333334rem" />
        <van-icon name="share-o" size="0.53333334rem" />
      </div>
    </div>

    <!-- 底部添加评论区域 - 2 -->
    <div class="cmt-box van-hairline--top" v-else>
      <textarea placeholder="友善评论、理性发言、阳光心灵" v-model.trim="content" @blur="blurFn" v-myfocus>
        </textarea>
      <van-button type="default" @click="publishFn">发布</van-button>
    </div>
  </div>
</template>

<script>
import { getCommentListAPI, commentLikeAPI, commentDisLikeAPI, publishCommentAPI } from '@/api/article'
export default {
  name: 'CommentList',
  data () {
    return {
      commentList: [], // 评论列表
      isShow: true, // 控制评论的textarea是否显示
      totalCount: '', // 评论数量
      content: '', // 评论的内容
      loading: false,
      done: false
    }
  },
  async created () {
    this.getCommentListFn()
  },
  methods: {
    // 获取评论列表
    async getCommentListFn () {
      const resp = await getCommentListAPI({
        artId: this.$route.query.id,
        offset: this.lastid
      })
      const { results, total_count: total, last_id: lastid } = resp.data.data
      // 判断后面是否还有数据
      if (lastid === null || results.length === 0) {
        this.done = true
        return
      }
      this.lastid = lastid
      this.commentList = [...this.commentList, ...results]
      this.totalCount = total || null
      this.loading = false
    },
    // 评论点赞
    async likeOrDislikeFn (obj) {
      try {
        obj.is_liking ? await commentDisLikeAPI({
          comtid: obj.com_id
        })
          : await commentLikeAPI({
            comtid: obj.com_id
          })
        this.$toast.success(obj.is_liking ? '取赞成功' : '点赞成功')
        obj.is_liking = !obj.is_liking
      } catch (error) {
        this.$toast.fail(obj.is_liking ? '取赞出错' : '点赞出错')
      }
    },
    // 滚动列表区域
    scrolllntoViewFn () {
      // ref不能跨文件获取dom
      // 原生dom可以跨vue文件获取dom
      document.querySelector('div.like-box').scrollIntoView({ behavior: 'smooth' })
    },
    // 文本域的失焦事件
    blurFn () {
      setTimeout(() => {
        this.isShow = true
      })
    },
    // 发布评论
    async publishFn () {
      if (!this.content) return
      try {
        const resp = await publishCommentAPI({
          artid: this.$route.query.id,
          content: this.content
        })
        this.commentList.unshift(resp.data.data.new_obj)
        this.$toast.success('发布成功')
        this.content = ''
        this.totalCount++
      } catch (e) {
        this.$toast.fail('发布失败')
      }
    },
    // 上拉加载更多
    async pullUpLoadMoreFn () {
      this.getCommentListFn()
    }
  }
}
</script>

<style scoped lang="less">
.cmt-list {
  padding: 10px;
  .cmt-item {
    padding: 15px 0;
    + .cmt-item {
      border-top: 1px solid #f8f8f8;
    }
    .cmt-header {
      display: flex;
      align-items: center;
      justify-content: space-between;
      .cmt-header-left {
        display: flex;
        align-items: center;
        .avatar {
          width: 40px;
          height: 40px;
          background-color: #f8f8f8;
          border-radius: 50%;
          margin-right: 15px;
        }
        .uname {
          font-size: 12px;
        }
      }
    }
    .cmt-body {
      font-size: 14px;
      line-height: 28px;
      text-indent: 2em;
      margin-top: 6px;
      word-break: break-all;
    }
    .cmt-footer {
      font-size: 12px;
      color: gray;
      margin-top: 10px;
    }
  }
}
/*美化 - 文章详情 - 底部的评论页面 */
// 外层容器
.art-cmt-container-1 {
  padding-bottom: 46px;
}
.art-cmt-container-2 {
  padding-bottom: 80px;
}

// 发布评论的盒子 - 1
.add-cmt-box {
  position: fixed;
  bottom: 0;
  left: 0;
  width: 100%;
  box-sizing: border-box;
  background-color: white;
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 46px;
  line-height: 46px;
  padding-left: 10px;
  .ipt-cmt-div {
    flex: 1;
    border: 1px solid #efefef;
    border-radius: 15px;
    height: 30px;
    font-size: 12px;
    line-height: 30px;
    padding-left: 15px;
    margin-left: 10px;
    background-color: #f8f8f8;
  }
  .icon-box {
    width: 40%;
    display: flex;
    justify-content: space-evenly;
    line-height: 0;
  }
}

.child {
  width: 20px;
  height: 20px;
  background: #f2f3f5;
}

// 发布评论的盒子 - 2
.cmt-box {
  position: fixed;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 80px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 12px;
  padding-left: 10px;
  box-sizing: border-box;
  background-color: white;
  textarea {
    flex: 1;
    height: 66%;
    border: 1px solid #efefef;
    background-color: #f8f8f8;
    resize: none;
    border-radius: 6px;
    padding: 5px;
  }
  .van-button {
    height: 100%;
    border: none;
  }
}
</style>
